Hattons announce 14xx / 48xx / 58xx

[BWsTrains]

Keith,

 

re your #1629 "The loco is tail heavy so there is no weight on the front driving wheels. No ifs, no buts, That's what my weight test shows."

 

sorry, your #1600 post was not clear to me and I'd missed the follow up explanation in #1622 of how you'd weighed the rear axle. So, I agree with the above

Having the CoG behind middle axle is hardly ideal for effective drive transmission, especially when they've gone to all that trouble plus inconvenience (loose Crank Rods) to get drive to the 4 wheels in the first place. Bizarre.

[brushman47544]

So what you're saying means that if the loco is properly balanced as supplied, adding a DCC decoder in the smoke box will change the centre of gravity probably to the detriment of traction capability.

 

If so then shouldn't manufacturers be ensuring that the blanking plug weighs about the same as a typical decoder?

Edited March 12, 2017 by brushman47544

[TerrySVR]

Is it worth buying one of these for layout without gradients I'm concerned it could end up parked in platform bay because of poor running. Maybe yes or no from those who own one.

 

Thanks in advance.

 

Terry

[Paul_sterling]

Surely gents, the static balance of the loco is rendered moot as soon as it has a load behind the bunker? though coaches don't act downwards on the loco, their resistive load on the drawbar combined with the directional rotation of the drivers will make the loco naturally sit down onto the rearmost wheels anyway, irrespective of how much nose weight (within reason) is available.

 

Paul.

[PMP]

Terry, yes.

 

I don't like the chassis design and the running isn't as good as a Hornby J15, but on a par with many other RTR models. Mine has improved slightly with extended running on rollers.

[Ian Hargrave]

Is it worth buying one of these for layout without gradients I'm concerned it could end up parked in platform bay because of poor running. Maybe yes or no from those who own one.

 

Thanks in advance.

 

Terry

Read post 1576 .To date no problems,including slow running.Remember DJM's specific reminder about "running in" (there is a reminder card when you open the box). Remember they are not suitable for use with a feedback controller as they have a coreless motor.My systen is DC analogue and I use a Gaugemaster controller.I suspect these models are perhaps less tolerant of track imperfections than some but nothing new there.

 

I understand your qualms as I read through this thread.Some members appear to have had certain issues with the model which is fair enough. I confess to believing that I may be the "odd man out" as I presently don't share their concerns. I sincerely hope there's no shame in that .There are a number of tube videos online,including this thread, that you can see to help in your decision making. At the end of the day,it's up to you,isn't it ?

[melmerby]

Keith,

 

re your #1629 "The loco is tail heavy so there is no weight on the front driving wheels. No ifs, no buts, That's what my weight test shows."

 

sorry, your #1600 post was not clear to me and I'd missed the follow up explanation in #1622 of how you'd weighed the rear axle. So, I agree with the above

Having the CoG behind middle axle is hardly ideal for effective drive transmission, especially when they've gone to all that trouble plus inconvenience (loose Crank Rods) to get drive to the 4 wheels in the first place. Bizarre.

If you have three suspension points which are rigid (no compensation, springs etc) there can only be weight on two of them unless the mass is distributed completely uniformly so that the centre of gravity is right in the middle.

 

In this case I cannot see why the decoder & socket which are relative lightweight couldn't have been sited at the rear and the whole of the smokebox filled with a metal plug

 

Keith

[melmerby]

Surely gents, the static balance of the loco is rendered moot as soon as it has a load behind the bunker? though coaches don't act downwards on the loco, their resistive load on the drawbar combined with the directional rotation of the drivers will make the loco naturally sit down onto the rearmost wheels anyway, irrespective of how much nose weight (within reason) is available.

 

Paul.

Ideally the loco should be front heavy so that all that happens is that more weight transfers to the rear drivers

A loco that is already tail heavy will just transfer weight to the non-driving trailing wheels, leaving less for adhesion.

 

Keith

Edited March 12, 2017 by melmerby

[tomparryharry]

I haven't got mine yet, so I'll reserve judgement on it's running qualities. I don't 'do' DCC, so I'd guess that there will be a lump of pb to go into the smokebox aperture. Likewise, the side tanks are an area where extra weight might be added, but not such to alter the bias away from the powered wheel sets.

 

I'm reminded of making an aged K's Dukedog kit, where the weight over the leading bogie was such that I had to put a spring in with the bogie pivot, to get it to run 'off it's nose'. It would appear such a spring might be needed to stop it from 'Dragging it's arse', although, as I've said, it's not here yet.

 

Time will tell, I'm sure.

 

Off to buy a good quality rolling road, methinks.....

 

Ian

[The Stationmaster]

Ideally the loco should be front heavy so that all that happens is that more weight transfers to the rear drivers

A loco that is already tail heavy will just transfer weight to the none driving trailing wheels, leaving less for adhesion.

 

Keith

 

A lot of logic in that but seemingly not the sort that Mr Collett, or his Drawing office staff agreed with, as the real 48/14XX were a little lighter on the front axle than they were on the other two ( 8cwt less in full working order).  The load on the other two axles was equal both empty and in full working order and would obviously vary as coal and water were consumed.  Obviously the difference in real life was very different from an even greater difference in a small scale model and if the load is greater on the rear axle than on the middle one then something is not right about the balance.

 

Is there a performance difference depending on which way the engine is being run?

[melmerby]

A lot of logic in that but seemingly not the sort that Mr Collett, or his Drawing office staff agreed with, as the real 48/14XX were a little lighter on the front axle than they were on the other two ( 8cwt less in full working order).  The load on the other two axles was equal both empty and in full working order and would obviously vary as coal and water were consumed.  Obviously the difference in real life was very different from an even greater difference in a small scale model and if the load is greater on the rear axle than on the middle one then something is not right about the balance.

 

Is there a performance difference depending on which way the engine is being run?

If the rear wheels had some springing it would move some of the adhesive weight onto the currently unloaded leading axle.

The thing that CBE had on his locos that models generally do not is compensated suspension so that axles can carry their fair share of weight. The chassis on a real loco is far from "rigid" and loadings can be adjusted to get the right balance.

I have heard of instances where locos such as "Kings", before adjustment, were found to be way out and one or more axles were well over the 22t 10c limit.

 

Keith

[PMP]

No difference on flat track, in reverse on Peco streamline CD75 curved points there is a noticeable V crossing strike. No issues on the medium/long/Y pointwork. The binding occurs on downhill gradients both 'ends', same for the J94. (3% gradient)

Edited March 12, 2017 by PMP

[JSpencer]

JSpencer,

 

I agree with most of your points. I was trying to get the principle clear and what we really need to further understand driving problems with 14xx is where is the GoG?

 

Where I disagree is with..

"If it is aft the second drivers, then we could find the front drivers with only 70 grams or less depending how far aft the weight is."

 

If the COG is behind the middle axis, then on perfectly level track there should be no effective weight bearing onto the front axle. This is Physics - the action of the COG is down from behind the centre axle transferring some share of the weight to the rear. Without flexing of the chassis there is no basis for any down action anywhere forward of the "pivot" i.e. centre axle as per my see-saw example. The lighter person on the see saw still has a mass of 50kg but that does not mean there is a weight of 50kg bearing down at that point. Their mass effective acts at the CoG

 

Don,t forget my scenario includes the middle drivers not touching the rails (please see the phrases before of my original post). I.e imagine a dip or the start of an incline. Once the middle drivers are clear of the track (tenth of mm is more than suffice) then all weight is on the front and rear axles only. There is no pivot in this scenario.

 

When the center wheels touch, even if the CoG is just aft the second drivers, say only 10% of the distance between it and the rear wheels! then on a 180 gram loco, we will have 162 grams acting over the drivers (mostly the second pair) and 18 grams on the rear wheels.

 

This too is physics, force times distance.

[JSpencer]

In a working model, surely function has to be a given and everything else a nice to have ? There were similar comments about the O2 that the weight was too far back.

Note: I am not stating the choice was correct, merely stating what the design intention was.

 

The O2, even if not as as heavy as possible, copes really well with any track work I throw at it. The rigid austerities from the same manufacturer are the most track sensitive models I have (practical if you wish to know if your track is perfectly laid).

 

At least if you don,t use DCC, you can fill the spaces with weights, which is easier than cutting lumps out to fit speakers.

 

I guess the best compromise would be removable weights.

[phil-b259]

In this case I cannot see why the decoder & socket which are relative lightweight couldn't have been sited at the rear and the whole of the smokebox filled with a metal plug

 

Keith

Because you would then not be able to fit a DCC decoder without dismantling the loco. Given the level of fragile detail fitted to models these days, lots of modellers moan about the need for fiddly dismantling to fit their decoder of choice.

 

The method chosen by DJM resolves this issue.

 

Perhaps it would be wise for contributors to this thread to remember that this is still a RTR model and fundamentally no different to those made by Hornby or Bachmann and the end result is thus always going to disappoint the section of the market that are fussy about matters such as weight distribution and drivetrain construction. It is an unfortunate fact of life that the more disconcerting the customer is, the less the size of said customer base, which then pushes up the costs of catering for said customers etc.

Edited March 12, 2017 by phil-b259

[Clearwater]

Heljan' 1366 sites the decoder in the bunker. Was a 2 min job to undo the four square headed screws and take the whole can unit off. No harder, 603 squadron excepted, than removing a tender top.

 

That said, I do like the DJM use of smokebox - a logical place for a decoder in my view

 

David

[PMP]

I make no apologies for being 'fussy' about drivetrain construction and design. I expect a model to work effectively up and down reasonable gradients as well as on level track. Neither this or the J94 should bind descending a gradient such as a helix for example.

 

Regardless of manufacturer that's a basic design fault.

[The Johnster]

I find myself agreeing with both phil- and PMP here.  This is an RTR model and manufacturers cannot cost such beasts to carry the same amount of detail as some kits, and at the same time an RTR model should run reliably on averagely laid track with curves and changes of gradient.  OT a little, but if a J94 is 'track sensitive' that is a very serious issue in what is a shunting locomotive whose function is to move wagons slowly around over pointwork in locations where tracklaying is likely to be less than perfect.

 

I have moaned about the weight of RTR plastic model small steam locos for years; there is no such thing as one that is too heavy and if the beast is so light on it's feet that the weight distribution can upset it...

Edited March 12, 2017 by The Johnster

[melmerby]

Don,t forget my scenario includes the middle drivers not touching the rails (please see the phrases before of my original post). I.e imagine a dip or the start of an incline. Once the middle drivers are clear of the track (tenth of mm is more than suffice) then all weight is on the front and rear axles only. There is no pivot in this scenario.

 

 

In this case the front drivers are carrying 87 grams and the trailing wheels 93 grams, using the same measuring equipment as before.

 

If the CoG was in front of the centre axle and the trailing wheels carried no load at all (like most RTR locos) and were free to move up and down, all the weight would always be on the driving wheels, no matter what.

That would be my ideal for a small 4 coupled tank.

 

Keith

[Captain Kernow]

Perhaps it would be wise for contributors to this thread to remember that this is still a RTR model and fundamentally no different to those made by Hornby or Bachmann and the end result is thus always going to disappoint the section of the market that are fussy about matters such as weight distribution and drivetrain construction. It is an unfortunate fact of life that the more disconcerting the customer is, the less the size of said customer base, which then pushes up the costs of catering for said customers etc.

That may well be, Phil, but it also a fact of life that everyone who is going to run this loco (as opposed to the possibly sizable proportion who will either display it in a cabinet or keep it in its box) has the right to desire their locos to run well and smoothly.

 

When all the other factors about the appearance of various parts of the loco have been taken into account, it is the running qualities that will determine whether I am ultimately happy with it or not.

[The Johnster]

Give me a slightly inaccurate model that runs well and starts reliably every time current is supplied to it, over a dead scale one that doesn't, any day!

Edited March 12, 2017 by The Johnster

[Fenway Park]

Following all the various "gates", I cancelled my pre orders with Hattons, but I still need a 58xx for my Cambrian project but I am still deterred by the chassis design with the apparent slop in the coupling rods etc. 

 

Shame as it looks so much better than the older Airfix/Hornby version.

[coachmann]

Fear not, the Hornby 14XX will be out sooner or later then we can start all over again...

[melmerby]

Fear not, the Hornby 14XX will be out sooner or later then we can start all over again...

I've still got two Airfix ones to go with the new Hattons variety!

 

BTW has anybody tried weighing the Hornby version with their smaller motor?

If so, Is it better balanced than the Airfix one?

 

Cheers

 

Keith

[JSpencer]

In this case the front drivers are carrying 87 grams and the trailing wheels 93 grams, using the same measuring equipment as before.

 

If the CoG was in front of the centre axle and the trailing wheels carried no load at all (like most RTR locos) and were free to move up and down, all the weight would always be on the driving wheels, no matter what.

That would be my ideal for a small 4 coupled tank.

 

Keith

I don,t dispute that.

 

My point was with the COG just aft, there will be - say - 90% of the weight over the second pair or just under half over the first pair depending on whether or not the second pair of drivers are in contact with the track or not. With big loads, one could quite easily find the model switching from sufficient strength to insufficient when it hits a dip. even here momentum would carry it through and I have not seen many (if any) comments about lack of haulage power. The model seems adequate to that task at least. 

Edit : If the COG is a 1/3 or 1/2 way between the second drivers and rear wheels, we will see either 2/3rds or 1/2 the weight on the second drivers. If the second drivers lift off due to a dip, the front drivers would find themselves with around only 20% of the adhesive weight.

 

Of course ideally, we would want the weight over the drivers and the rear axle sprung (like the well tank is only reversed). This has to be matched with the DCC requirement, maybe the chip can go over the motor or in the side tank and the speaker in the bunker. Maybe not. We do not know what alternatives were reviewed when the model was designed.

Personally I am a big fan of sprung axles. For example I find Bachmann's 8750 runs better with one, than Bachmann's 64XX which is without, despite the two models being a similar size and weight. The DJM Well tank - with sprung axle - runs better than the DJM austerity without and also better than Bachmann's USA tank without. When I say better, it should be noted that the differences are marginal.

 

On the other hand, the Model Rail sentinel (distant ancestor of the Well tank, Austerity and 14XX) with its 4 rigid wheeled chassis shows excellent performance even over point work, capable of 9 Bachmann Mk1's on the flat. It is heavy for a small loco though as its cube like interior is simply full of weight.

Edited March 13, 2017 by JSpencer